P2.117 Wednesday, Jan. 5 VASOPRESSIN AND PITUITARY ADENYLATE CYCLASE-ACTIVATING POLYPEPTIDE (PACAP) PARTICIPATE COOPERATIVELY IN BEHAVIORAL AND NEUROENDOCRINE RESPONSES TO ENVIRONMENTAL DEMANDS VALDEZ, Matthew*; BEITZEL, Christy; SHAHIDIZADEH, Anoush; VALDEZ, Joseph; MARTINEZ, Bathann; SPURGIN, Kurt; KAPRIELIAN, Antony; ABAD, Catalina; WASCHEK, James; CURRAS-COLLAZO, Margarita; University of California, Riverside; University of California, Riverside; University of California, Riverside; Moreno Valley Community College; University of California, Riverside; University of California, Riverside; University of California, Riverside; UCLA; UCLA; University of California, Riverside firstname.lastname@example.org
PACAP and its receptors are required for vasopressin (VP)-mediated osmoregulation (Gillard et al, 2007). Recently, we have shown that PACAP-deficient mice show aberrant VP and nitric oxide (NO) release from magnocellular neuroendocrine cells (MNCs) in supraoptic tissue punches challenged hypersosmotically (Shahidizadeh et al, 2009). In the present study, PACAP KO mice 2g% NaCl drinking X 7 d did not show the stimulated NO release evident in WT (48.5+4.6 vs. 230.9+52.1% of WT normosmotic, p=0.03, n=11). Central VP release from MNCs has been implicated in neuromodulation of distant circuits associated with stress, learning and affiliative behaviors (Landgraf, 2005). Interference of VP or PACAP signaling can reduce anxiety-related behavior (Landgraf et al. 1995; Hashimoto et al, 2001). Using an elevated plus maze we show an increased open arm time for PACAP KO vs WT: 81.4+14.3 vs. 47.5+10.9 sec, respectively (p<0.07, n=16. Next, we subjected PACAP KO mice to an olfactory-driven social discrimination task which used gonadally intact females presented within corrals inside clean test cages (MacBeth et al, 2009). Compared to WT, PACAP KO male mice were unable to discriminate a novel from a familiar female since time spent investigating novel or familiar females was not different: 47.3+2.9 and 45.9+5.7 sec, respectively (p=0.83, n= 8). Therefore, VP and PACAP neuropeptide systems work collaboratively at multiple nervous system levels.